There's all sorts of various levels of modding experience.

Essentially the vanilla game is just a collection of files, textures, meshes, animations, sprites, and code, which all get put together via the directions to form the games infrastructure.

Mods and modders are able to take that, break it down, analyze it, and add in or add to the existing framework. This can be done to simply tweak certain values, to make the game easier, lazier, or hard; it could just be to make it cosmetically more appealing; or it can take the gameplay in new directions with new and extra content.

Its not exactly a simpler process for the casual user to jump into though; one must learn or know what they're doing in order to actually succeed in installing or creating a mod as intended, without instead breaking the game. The difficulty of modding certainly is not based on the simplicity or complexity of the feature, as it depends on how the file infrastructure provided is utilized (ie, changing a specific texture color from say blue to red sounds simple, but is surely more complex than changing numerical values say to cheat up your character skills). The developers created the basket that is the game, and filled it with fruit that is the content... and modders can take that fruit and play with it or even to the point of adding in different fruit (ie content).


The issue here is, Valheim is a popular enough game that the community and the modding community with it is in danger of outpacing the actual development vision of the original dev team (or in this case, more like rocketing past on the dev's rocket fuel...). Cries and demands for "why don't you add X in" will always overwhelm those who need to consider what to actually add in, which just leaves a few, more capable modders with some more ambition to fill that niche on their own. The problem with that then, is that players and users of mods may just find more disappointment when the developers actually do get around to creating more content, in that it already wouldn't be enough to satiate what modded content playthroughs have already surpassed. And heaven forbid a developer should change anything that messes with the meta of the game's current or prior flow (ie, stamina complaints), despite the fact that it is a developing early access game, with the expectations that broken features also get fixed, or that new content added in may require a rebalancing of the older game content as well.